Improving the Environmental Sustainability of Flash Geothermal Power Plants—A Case Study

The sustainability of geothermal energy production is analyzed with reference to a production plant located in a specific area (Monte Amiata, Italy). Four solutions combining a flash power plant with an Organic Rankine Cycle in a hybrid configuration are analyzed in terms of production of electricity, exergy balance and emissions level (CO2, H2S, Hg).. The different solutions correspond to increasing environmental performance, and for the most advanced case achieve near-zero emissions (complete reinjection of the natural resource, including incondensable gases). The results show that this can be achieved at the price of a progressive reduction of electrical productivity.